The Good C, Vitamin C Serum is Dr. Barbara Sturm’s newest serum containing a unique mixture of Vitamin C in three skin-friendly forms and concentrations. Zinc acts as a booster that transports the Vitamin C effectively into the skin. The serum helps to reduce uneven pigmentation, improve tone, stimulate collagen and hyaluronic acid synthesis and provides anti-oxidative protection from free radicals and UV stress. THE GOOD C VITAMIN C SERUM was developed to infuse skin-beneficial properties of Vitamin C into the skin, without harming it. The active ingredient complex includes Cockatoo Plum, oil-soluble Vitamin C THD and stabilized, synthetic Vitamin C in glucosidic form. THE GOOD C VITAMIN C SERUM contains a concentration of 5% Vitamin C that is safe and gentle on the skin. Higher concentrations do not remain stable on the skin, eventually causing inflammation and damaging the skin barrier function.